Is a spell focus or anchoring focus considered active when it's 'standing by' but not really doing anything? For example, Bob the mage has magic 5. He has a force 4 sustaining focus that has, say, Armor. He has a force 4 specific spell focus for Manabolt, and a force 4 anchoring focus for Treat. If he uses his force 4 spell focus for a Manabolt, then much later in the turn his anchoring focus goes off, was his total active foci used at 12, or was it at 8 twice? (sustaining and specific spell, then later sustaining and anchoring)
ref MitS pg 45-46

OK, from the strict wording of the rules, the trigger is total Force twice Magic Attribute, but the TN is made against 1/2 Force of active foci.

Was my grammar really that bad?
Yes, the trigger is 10, and the TN is half active, no questions there. The question is, did Bob ever actually reach the trigger? Was he using a total of 12 points (and thus have to roll against TN6), or did he have 8 points active on two different occasions? (and thus have no need to roll at all)

Moon-Hawk: according to your example, he had an anchoring and sustaining focus active (Force:4 each), and then he activated amd uses a specific spell focus (Force:4). So at the moment of he activated the specific spell focus, he had 12 Force of foci active at once, he needs to roll. If the anchoring focus goes off in the same combat turn, then he has only 8 Force worth of foci active, and has a TN of 4.

Anchoring Focus:
Once the spell(s) are linked to the anchor, the anchor is active. ("Using an Anchoring Focus", MitS.71).

Therefore, even though the Treat spell has not yet been triggered the anchoring focus counts toward focus addiction all the time you've got it ready to use.

Spell Focus:
You must activate the Spell Focus (a simple action) prior to using it to cast a spell. ("Activation", SR3.190). Therefore it's active all the time you're walking around with it ready for use.

Focus Addiction:
At the end of each Combat Turn, add up the total rating of all the foci you used during that Turn. Include Expendable Spell Foci too, even though it takes no Karma to bond them. Even if you never had more than one on at a time, if the total for the Combat Turn is greater than twice your magic rating....

Okay, cool. The anchoring focus was a bad example, I realized that a moment after I posted. So changing the example a bit: If the example was a force 4 sustaining, and two force 4 specific spell foci. The first specific spell focus could be activated, the spell cast, and deactivated, then the second was activated, spell cast, and deactivated (he must have a very high initiative, but whatever) he STILL has to check for magic loss, right?

My first instinct is to say no-- but then again, it takes an action to activate a focus, so what you describe isn't going to happen for a mage of normal speeds.

Cain: The speeds involved aren't all that ridiculous. I mean, they are, as I put it before, but the first spell focus could be active from the turn before, so that's a complex action to cast a spell and a free action to deactivate the focus, second pass is a simple action to activate the other focus, and even without the third pass to cast the second spell we've had a total of 12 points worth (including the sustaining focus) active in this turn, but never more than 8 at a time. For that matter, you could spend your whole turn turning them on and off without ever actually using any of them, but that's just silly.
As for total vs instantaneous ratings, I can see rationalizations for ruling it either way.
OurTeam: Thanks for the feedback. I agree that the first part of that passage seems to imply checking that way, but then at the end of the round your target number is half the rating of all "active" foci. At the end of the round, there aren't 12 active, there are only 4 or 8 points active, so I feel like that part of the passage sort of implies that we're only talking about those foci that are simultaneously active.
Ancient History: I like that solution, sort of a best of both worlds thing, where yes, you have to make the check, but the target number is very low. But would you have it the same way if it were two specific spell foci instead of a spell and an anchoring? (which is my mistake for using that as an example, sorry)

I guess I just feel like that passage is a bit vague, and was wondering how it had been ruled by others. Thanks for feedback, all, hoping for more.

Dunno where you're really having the problem. Any time you simultaneously exceed the allowed limit, you have to check for Focus Addiction. It doesn't matter if you're using some new kind of focus that only takes a thought to activate and deactivate; if its active and pushes you over the limit, bam, you're checking for addiction. If at any point you're not over the limit because you have some deactivated, duh, you don't check.

Where's the confusion?

The problem is, you're making assumptions. No where in the focus addiction section is the word 'simultaneously' used. The word 'total' implies that it is cumulative.
Personally, I think it should be the simultaneous version, but I'm asking for other interpretations.

Err, "total" doesn't imply simultaneously, it means simultaneously. You can't have a total unless you add more than one thing up. But sure, Shadowrun's never been known for its wonderfully worded rules, either.

I agree with ACL on this one. I've always run it that you have to have a total force in foci greater than twice your magic attribute active simultaneously in order to check for addiction. So, Bob would not have to check, if I read your example correctly. But, if he had two force 4 sustaining foci and then used a force 4 expendable spell focus, he'd have had a total of 12 force "points" of foci at one time and would have to check for addiction.

If you read the Focus Addiction example on MitS p. 46, you'll see that OurTeam is dead on. Its cumulative for all the foci you have active during the round, whether they're used simultaneously or not. But the simultaneous way seems more fair to me. I'd probably do that, unless I'm having a real problem with players using way too many foci. Then I might hit them with the cumulative ruling.

Also, how do you deal with Allies? They can act like a power focus, right? So do they count towards the limit or are they a "free" focus that doesn't count towards addiction? I mean, technically, the magician is relying on something other than himself to generate more powerful magic. But I suppose it could be argued that an ally, since its paid for from the magician's own magic, is part of him... That could really limit the power of allies - if you use a lot of foci, you don't want an ally that could push you over that focus addiction limit. But if they're a "free" power focus, that could make them really bad-ass. Hmmm. I never really thought about it.

Here's the way I read the rules on this:

If you have a magic of 6, then you can use/have active up to 12 Force worth of foci without penalty, in any combination. So if I want to keep my Force 6 power focus and Force 6 weapon focus on at all times, I'm cool as long as I don't use any other foci.

So, during a combat turn (the sum of all combat phases for one round of combat), I can have magic x 2 foci active, any more and I have to test. The test target number is determined by how many foci I have active at the end of the combat turn (which can be rationalized). Which depends on how many actions the player takes to deactivate or activate foci, expendable spell foci or anchoring foci used, and whether any foci are destroyed, blocked, or seperated from the magician (which means they deactivate immediately).

Let's take a quick example:
I have a magic of 6; and a Force 6 power focus active. I have three combat phases(rolled really high).

During phase 1, I draw a Force 4 expendable spell focus and rip out a monster fireball spell, discarding the burntout expendable spell focus.

During phase 2, I draw my Force 6 weapon focus and activate it.

Between phase 2 and 3, a magician manages to block, destroy or remove my power focus from me.

During phase 3, I stick my weapon focus through the offending magician, then take a free action to deactivate it.

End of combat turn. I've used 16 Force worth of foci, I need to make an addiction test. However, none of the foci are currently active, so my TN is 0. Next combat turn, I need to reactivate/recover any foci I want to use.

At least, that's my take on it.

Prospero: I treat allies as separate from foci. They cost so muck karma to create and maintain that I don't see an imbalance in that part.

Ally spirits aren't foci. They have an ability that functions in a fashion similar to a power focus, but by no means are they a power focus.

I interpret "make a Magic Test against a target number equal to half the total Force of the active foci (round down)..." to mean all of the foci that were active during the round. Otherwise, a mage with a high initiative and several actions could get really cheesy. First action: with your Force: 6 manabolt focus already active, activate your Force: 9 manabolt focus. Second action: use both foci, as well as your Force: 8 Expendable Combat Spell Focus, to cast the mama of all manabolts. Third action: deactivate both foci. Make a Focus Addiction test at TN: 0.

Can I have some nachos with that cheese?

I run it the way Glyph describes. I think that is what the authors intended.

@Cain: Karma-wise, they don't necessarily have to cost more than a power focus. Power foci are force*5 to bond and that's what you pay for allies. Now, all the rest of the stuff magicians often buy for them can get expensive (skills, spells, attributes, etc) if you want it to. But if someone wanted to have a free power focus, they could just wait until their next initiation and summon an ally with it for about the same karma as the focus would cost. Plus they can get a lot more use out of the spirit. Of course, it might get pretty pissed if they didn't put any more karma than that into it over time, but unless they're terrible at summoning or the ally is really high force, it probably isn't going to go free.

Having said that - I'd probably do it your way (I _do_ do it your way, actually). But its still a valid argument.